Of course you can blame him, he did wrong and his thinking was wrong. You need good education to make good decisions, something that he did not have or people like him don't have. What can you do with a couple hundred or thousand dollars? Nothing!! You spend it fast, it is useless money. So is it better to risk this money going to zero for a chance to have life changing gains? Of course it is. You need to know how to analyze risk reward ratios, that is his mistake. I'd rather my current holdings go to zero than to miss out on changing my whole life.
Blame him for not buying Bitcoin at around 2$? I don't see why you should blame him. You might think it's just a few dollars but there are people who do not invest in what they don't trust regardless of the amount. I don't trust many low cap altcoins and some of them are below a dollar.
Because Bitcoin was very low then doesn't mean he must buy it. I still think you can only blame him when he did not get it later on when he saw the price going up. If he miss it at $2 he may have gotten it at $17 or anything below $20 which if held till now is a win.